This spring the American College Theater Festival, in its 11th year, will celebrate with a new stage -- the Kennedy Center's Terrace Theater -- four new-play productions, a televised adaptation of the winning student play and a visit from Lynn Fontanne.

This year's festival, which runs from April 16 to May 6, will present eight productions in the finals of college theatrical productions that have played to a national audience of more than 2 million this year.

At the press conference and preview yesterday, Washington's WRC-TV announced that it will show a television adaptation of "The Authentic Life of Billy the Kid," the play that won the top student playwriting award for Lee Blessing, of the University of Iowa Theater. It will be taped in the Terrace Theater here for showing later. Amoco, which has been the corporate sponsor for the American College Theater Festival for nine years, will also sponsor the television adaptation.

The appearance of Lynn Fontanne, one of the great leading ladies of the American stage, is scheduled for the performance competition for the Irene Ryan Winners Circle Acting Award on April 22. Fontanne, now in her 90s, will appear with Richard L. Coe, drama critic emeritus of The Washington Post, who will be special guest host.

Half of this year's productions -- four of the eight shows -- will be new plays, the largest number ever presented at the festival.

Among the finalists, chosen after regional competition, is the drama troupe from the University of Maryland in Baltimore County. The students will be doing "Five by Beckett," a collection of short plays rarely performed.

Other finalists and productions include "Look Back in Anger," the play about the angry young men of Britain of the '50s from the perspective of 1979, from Wright State University, Dayton, Ohio; "Summer of the Seventeenth Doll;" from Hofstra University; and "LuAnn Hampton Laverty Oberlander," one of Preston Jones' "Texas Triology," from the University of Florida at Gainesville

In addition to Blessing's winning student play, the festival's other new plays by students include "And They Dance Real Slow in Jackson," written by James Leonard Jr., which had its premiere at Hanover College in Hanover, Ind.; "Engendered Species," by Richard Larson, presented by the UCLA drama group; and "Waiting for the Feeling," an original collaborative musical from students at Brandeis University.